1. Field of the Invention
The invention relates to a zoom button structure. More particularly, the invention relates to a zoom button structure applicable to a portable electronic device such as a camera, a camcorder, or a mobile phone or the like.
2. Description of Related Art
Portable electronic device such as camera, camcorder or mobile phone in present-day often uses a middle band to fix the zoom button onto the main body of the portable electronic device so that users can conveniently adjust the focus. In general, the manufacturing process of the middle band is as follows: first fabricating mold, then injection molding and finally electroplating. However, the middle band is often in an irregular structure. That is, some holes or grooves to adapt with the electronic device such as zoom button, power plug hole and signal transmission plug hole are often disposed at the middle band. The more complicated the structure is, the complexity of the fabrication of mold would be increased. For injection molding, the required pressure holding time would be increased, and the cycle time and the complexity of the injection molding process are also increased if the molding structure is complicated. In addition, the larger the middle band, the higher the cost for molding is needed. The cycle time and the complexity of the injection molding process are also increased. Furthermore, the middle band is often in a slender structure and in a U-shaped or a quadrilateral frame. In general, the quality of the electroplating process would be decreased in the U-shaped electroplate, and it leads to the demand of improving the electroplating technique. The quality of the electroplating process is seriously decreased if the electroplate is a quadrilateral frame. Additionally, for the zoom button structure in present-day, components are separately formed and assembled. That is, besides the twisting element for zooming, a metal plate is further needed to screw up to the twisting element for zooming with a screw. After assembling such configuration, if the metal plate is exerted an external force, deformation is easy to occur due to the deficiency of the structural strength of the zoom button. And it may lead to loosening and quality of the whole electronic device becomes lower.
Specifically, for the conventional zoom button structure, the middle band is often an integrally formed electroplated middle band and the zoom button is the assembly of the metal plate and screw. Since many parts are needed and the structural strength is not enough in the conventional zoom button structure, the complexity, labor hour and cost of the fabricating process is increased.